A lever system generates the force provided by the bucket to open the valve against system steam pressure. The mechanism is free-floating and has no fixed pivots to create wear or friction.

Because the mechanism is located at the top of the trap, no dirt can collect on the orifice. Small particles of dirt are held in solution until discharged by the full inlet pressure purging action when the bucket sinks, pulling the valve off its seat.

The discharge orifice is surrounded by a liquid seal, which prevents live steam loss. Automatic air venting is provided by a small vent hole in the bucket, which allows continuous automatic air and non condensed gases to vent at saturated steam temperature.